**14. SPACE**

Stent-protected angioplasty versus carotid endarterectomy in symptomatic patients included 1183 patients with symptomatic carotid-artery stenosis. Patients were randomly assigned within 180 days of transient ischemic attack or moderate stroke (modified Rankin scale score of < or =3) to carotid-artery stenting (n=605) or carotid endarterectomy (n=595). The primary endpoint of this hospital-based study was ipsilateral ischemic stroke or death from time of randomization to 30 days after the procedure. The non-inferiority margin was defined as less than 2.5% on the basis of an expected event rate of 5%. Analyses were on an intention-to-treat basis. The rate of death or ipsilateral ischemic stroke from randomization to 30 days after the procedure was 6.84% with carotid-artery stenting and 6.34% with carotid endarterectomy (absolute difference 0.51%, 90% CI -1.89% to 2.91%). The one-sided p value for non-inferiority is 0.09. SPACE failed to prove non-inferiority of carotid-artery stenting compared with carotid endarterectomy for the periprocedural complication rate.[20]

Lon term data showed that in both the intention-to-treat and per-protocol analyses the Kaplan-Meier estimates of ipsilateral ischemic strokes up to 2 years after the procedure and any periprocedural stroke or death do not differ between the carotid artery stenting and the carotid endarterectomy groups (intention to treat 9 5% vs. 8 8%; hazard ratio (HR) 1 10, 95%CI 0 75 to 1 61; log-rank p=0 62; per protocol 9 4% vs. 7 8%; HR 1 23, 95%CI 0 82 to 1 83; log-rank p=0 31). In both the intention-to-treat and per-protocol populations, recurrent stenosis of 70% or more is significantly more frequent in the carotid artery stenting group compared with the carotid endarterectomy group, with a life-table estimate of 10 7% versus 4 6% (p=0 0009) and 11 1% versus 4 6% (p=0 0007), respectively.[21]
